An accessory, such as a necklace, a bracelet, or an anklet, which is worn in a circular state includes a pair of coupling members that are respectively provided at a first end portion and second end portion of the accessory, in order that the first end portion and the second end portion are coupled to each other. To be specific, when wearing the accessory around a neck, an aim, or the like, the coupling member provided at the first end portion of the accessory and the coupling member provided at the second end portion of the accessory are coupled to each other, so that the accessory forms a circular shape.
For example, in the case of the necklace, the necklace is worn by coupling the coupling members at the back of (at the rear side of) the neck, that is, at a position that is out of sight. Normally, these coupling members are extremely small. Therefore, when coupling both end portions of the necklace to each other, a wearer has to do detailed work.
To reduce complexity of the work done when wearing the necklace, the following coupling structure has been proposed. To be specific, proposed is a coupling structure configured such that: an inserting portion that is the coupling member formed at the first end portion of the necklace is inserted into an insertion hole portion that is the coupling member formed at the second end portion of the necklace; the inserting portion is rotated to be positioned; and in this positioned state, the inserting portion is further inserted into the insertion hole portion to be coupled to the insertion hole portion (see PTLs 1 and 2, for example).